{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "d5e03cbb0c88cd1be39f2adc37d602230045964b"
            },
            {
              "fixed": "0d5fcb063cdabb9aeaa8554b7fedad2092c4150e"
            },
            {
              "fixed": "9e9fb259bcddf459a0168f4a964e979e500a68a5"
            },
            {
              "fixed": "bf5b609524497c195f801cd5707252384aed8149"
            },
            {
              "fixed": "aec095f3cc6cf209effd93278ce35be27db81d73"
            },
            {
              "fixed": "270564513489d98b721a1e4a10017978d5213bff"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.17.0"
            },
            {
              "fixed": "6.6.128"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.75"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.16"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43288.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: move ext4_percpu_param_init() before ext4_mb_init()\n\nWhen running `kvm-xfstests -c ext4/1k -C 1 generic/383` with the\n`DOUBLE_CHECK` macro defined, the following panic is triggered:\n\n==================================================================\nEXT4-fs error (device vdc): ext4_validate_block_bitmap:423:\n                        comm mount: bg 0: bad block bitmap checksum\nBUG: unable to handle page fault for address: ff110000fa2cc000\nPGD 3e01067 P4D 3e02067 PUD 0\nOops: Oops: 0000 [#1] SMP NOPTI\nCPU: 0 UID: 0 PID: 2386 Comm: mount Tainted: G W\n                        6.18.0-gba65a4e7120a-dirty #1152 PREEMPT(none)\nRIP: 0010:percpu_counter_add_batch+0x13/0xa0\nCall Trace:\n \u003cTASK\u003e\n ext4_mark_group_bitmap_corrupted+0xcb/0xe0\n ext4_validate_block_bitmap+0x2a1/0x2f0\n ext4_read_block_bitmap+0x33/0x50\n mb_group_bb_bitmap_alloc+0x33/0x80\n ext4_mb_add_groupinfo+0x190/0x250\n ext4_mb_init_backend+0x87/0x290\n ext4_mb_init+0x456/0x640\n __ext4_fill_super+0x1072/0x1680\n ext4_fill_super+0xd3/0x280\n get_tree_bdev_flags+0x132/0x1d0\n vfs_get_tree+0x29/0xd0\n vfs_cmd_create+0x59/0xe0\n __do_sys_fsconfig+0x4f6/0x6b0\n do_syscall_64+0x50/0x1f0\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n==================================================================\n\nThis issue can be reproduced using the following commands:\n        mkfs.ext4 -F -q -b 1024 /dev/sda 5G\n        tune2fs -O quota,project /dev/sda\n        mount /dev/sda /tmp/test\n\nWith DOUBLE_CHECK defined, mb_group_bb_bitmap_alloc() reads\nand validates the block bitmap. When the validation fails,\next4_mark_group_bitmap_corrupted() attempts to update\nsbi-\u003es_freeclusters_counter. However, this percpu_counter has not been\ninitialized yet at this point, which leads to the panic described above.\n\nFix this by moving the execution of ext4_percpu_param_init() to occur\nbefore ext4_mb_init(), ensuring the per-CPU counters are initialized\nbefore they are used.",
  "id": "CVE-2026-43288",
  "modified": "2026-07-08T05:38:08.214739488Z",
  "published": "2026-05-08T13:11:13.195Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0d5fcb063cdabb9aeaa8554b7fedad2092c4150e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/270564513489d98b721a1e4a10017978d5213bff"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9e9fb259bcddf459a0168f4a964e979e500a68a5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/aec095f3cc6cf209effd93278ce35be27db81d73"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bf5b609524497c195f801cd5707252384aed8149"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43288.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43288"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "summary": "ext4: move ext4_percpu_param_init() before ext4_mb_init()"
}